London has been battered by 50mph winds that have felled trees and caused travel chaos. Powerful gusts swept across the capital as the Met Office issued a yellow "be aware" weather alert for most of the country.

President Obama returned to the campaign trail vowing to end political point-scoring after Superstorm Sandy — but the truce did not last long.

The spirit of national consensus soon descended into bitter rhetoric as the President and Republican challenger Mitt Romney both tried to boost their support before Tuesday’s election. Mr Obama told a rally in Green Bay, Wisconsin, early yesterday: “There are no Democrats or Republicans during a storm, just fellow Americans. All the petty differences that consume us in normal times seem to melt away.”

He praised the “leaders of different parties working to fix what’s broken”. But the goodwill faded over the day.

Mr Romney took a dig at the President and Mr Obama retaliated before both sides released aggressive television adverts attacking each other.

The politicians’ new confrontational tone was repeated by ordinary Americans on the streets. State troopers were sent to quell disturbances as the east coast battled to recover from the devastation wreaked by Sandy.

Two-thirds of New York’s petrol stations remained closed, causing tempers to boil over. Fuel shortages across the city and in New Jersey caused fights at filling stations amid long lines of cars and people with jerry cans.

Power suppliers also warned that some areas might not have electricity for another 10 days. Residents even set up communal phone-charging points so people can use their mobiles.

But there were still some reassuring sights amid the chaos as New York citizens organised hot food outlets on the streets for those worst hit by the storm — and postal workers delivered mail to homes in wrecked streets.

The death toll from Sandy today passed 90 and is expected to rise. Millions are still without electricity and the damage caused by the superstorm will cost an estimated £30 billion.

Back on the election campaign, polls show the race is too close to call — and the challengers will spend the final days in eight swing states that will decide who captures the White House.

Mr Romney had toned down his remarks in Sandy’s immediate wake in case he was accused of playing politics during the disaster.

But last night he was back on the warpath, blasting Mr Obama’s campaign for running out of ideas. “Unfortunately what you’ve seen is a campaign that keeps on shrinking,” he said.

He also criticised the President’s plan to create a business czar, saying: “I don’t think adding a new chair in his Cabinet will help to add millions of jobs on Main Street.”

Mr Romney said at a window factory in Roanoke, Virginia: “We don’t need a secretary of business to understand business. We need a President who understands business — and I do.”

The President told supporters in Green Bay: “He’s saying he’s the candidate of change. Well, let me tell you, we know what change looks like and what he’s offering isn’t change.”

Mr Obama received a boost when he was endorsed by New York’s independent mayor Michael Bloomberg, who said he believes the Democrat will do more to tackle climate change.